1. Field of the Invention
The present invention generally relates to a socket connector, and in particular to a simplified socket connector mounted to a circuit board which replaces a base thereof.
2. The Prior Art
A socket connector, such as Zero Insertion Force (ZIF) connector is often used to connect a central processing unit (CPU) module to a circuit board. As shown in FIG. 1 of the attached drawings, a known socket connector 7 comprises a base 74 fixed on a circuit board (not shown) and a cover 71 mounted to the base 74 with a slide plate 72 movably received therebetween. A manual driving member 73 is pivotally supported between the cover 71 and the base 74 and is drivingly coupled to the slide plate 72 for moving the slide plate 72. The manual driving member 73 partially extends beyond the cover 71 for facilitating manual operation thereof. The rotation of the manual driving member drives the slide plate 72 to move with respect to the base 74 and the cover 71.
Contact elements 75 are received in bores 741 defined in the base 74. The cover 71 defines a plurality of holes 711 corresponding to the contact elements 75 for receiving pins of a CPU module (not shown) therein. The pins are partially received in corresponding slots 721 defined in the slide plate 72 whereby the movement of the slide plate 72 causes conductive members (not shown) retained therein to simultaneously engage with the pins and the contact elements 75.
The contact elements 75 are soldered to the circuit board by a solder ball technique and during the soldering process, heat is simultaneously applied to the base 74 and the circuit board which both undergo thermal expansion. Since the base 74 and the circuit board are often made from different materials having different thermal expansion coefficients, a relative shift occurs between the base 74 and the circuit board causing the solder balls to be undesirably displaced or damaged.
Furthermore, the base 74 shields the engagement between the contact elements 75 and the circuit board whereby it is difficult for a user to inspect and ensure a proper soldering engagement between the contact elements 75 and the circuit board.
Thus, it is desired to have a socket connector that eliminates the problems discussed above.